Stop motion system for strand-handling machine

ABSTRACT

A stop motion for a strand-handling machine that includes a yoke which both guides the strand emerging from the machine and houses the stop motion system. Presence of a certain amount of strand in the yoke prevents excitation of the stop motion system. The yoke assumes the appearance of an inverted &#39;&#39;&#39;&#39;U&#39;&#39;&#39;&#39; and houses the stop motion system in one or both of the legs that depend downwardly from the top of the yoke. When too little or no strand passes through the yoke, the particular stop motion system being employed becomes excited and actuates the stop motion circuitry to shut down the machine or signal for corrective action. A strand monitor wheel is also provided in combination with the yoke to continuously monitor the strand being produced or handled by the machine and simultaneously to serve a stop motion function.

United States Patent llllllllll Primary Examiner-William M. Shoop, Jr. Att0rneyWellington M. Manning, Jr.

Edwin A. Snape, Ill, Easley, both of, S.C. Appl. No. 881,563 Filed inventors Clair W. Schwalm Greenville;

Dec. 2, 1969 Patented Aug. 31, 1971 Benjamin Booth Company Philadelphia, Pa.

STOP MOTION SYSTEM FOR STRAND-HANDLING 1 [73] Assignee ABSTRACT: A stop motion for a strand-handling machine that includes a yoke which both guides the strand emerging from the machine and houses the stop motion system. Presence of a certain amount of strand in the yoke prevents excitation of the stop motion system. The yoke assumes the appearance of an inverted U and houses the stop motion system in one or both of the legs that depend downwardly from the top of the yoke. When too little or no strand passes through the yoke, the particular stop motion system being employed becomes excited and actuates the stop motion circuitry to shut down the machine or signal for corrective action. A strand monitor wheel is also provided in combination with the yoke to continuously monitor the strand being produced or handled by the machine and simultaneously to serve a stop motion function.

PATENTEU M1831 I971 sum 1 OF 3 FIG.

INVENTOR. CLAIR W. SCHWALM m WY E I D. M m A m W D PATENTED M163] 1971 SHEET 2 BF 3 FIG. 2

INVENTOR. W. SCHWALM NZA. S NAPE 1J1 ATTORNEY PATENIED was] I971 sum 3 0r 3 mo u 0 OON STOP MOTION SYSTEM FOR STRAND-HANDLING MACHINE BACKGROUND OF THE INVENTION Stop motions of various designs have been used in the textile industry for many years. Many of these stop motions depend upon the presence of strands of yarn, roving, sliver, or the like to prevent their actuation and therefore maintain the normal operation of the machine that is producing the yarn, roving, sliver, etc. Stop motions are used for several reasons. Normally the stop motion is employed to indicate a malfunction in machine operation or defective product produced thereby, to anticipate a malfunction and initiate the necessary corrective measures when the malfunction or a suggestion of the malfunction is detected, and to reduce downtime of the machine. Accordingly, less inferior or offgrade product is produced, machine damage is prevented and most importantly, production efficiency of the machine is improved.

As the textile industry has developed and the state of the art advanced, so has the state of the art of stop motions for the textile industry advanced. Stop motions first began in a mechanical environment, followed by a mechanical electrical environment and have progressed to the present day pure electrical or optical electrical environments. In early stop motions the pressure of the product on a lever, for instance, prevented actuation of the stopping mechanism. Such devices possess inherent disadvantages in that the lever can be propped up and out of operation or that fly and lint in the air can collect around the pivot points of the lever and inadvertently wedge the lever away from the actuating device. Further, fly, lint, oil and the like are subject to render most systems inoperative through impedance to mechanical movement; distortion of optical purity; change of electrical resistance of a conductor, and the like, unless removed from the surroundings. Accordingly, it is incumbent for successful operation of a stop motion to avoid these aforementioned problems. The present invention affords a stop motion that does overcome the above-mentioned problems and disadvantages of the previously discussed stop motions and will continue to function properly even under the most adverse conditions.

As to the present stop motion, the prior art does teach a variety of stop motions, but none of the prior art teaches or suggests the present invention, nor is there a combination of prior art that would render the present invention obvious to one skilled in the art. Exemplary of the prior art, U.S. Pat. Nos. are Hepp et al. 2,438,365; De Santis et al. 2,636,223; De Lathauwer, 2,694,838; Hunter et al. 2,759,225; Wilson, 2,936,51 l; Schacher, 3,158,852; Burnham, 3,268,953; Dornberger, 3,287,887; Stutz, 3,298,401; Binder et al. 3,300,817; Martin, .lr., 3,317,734; and King, 3,391,840.

SUMMARY OF THE INVENTION The present invention relates generally to a stop motion system for a strand-handling machine comprising a yoke, said yoke having an apex and two leg portions depending therefrom, said apex and said leg portions defining a strand passage, at least one of said leg portions having incorporated therein a strand-sensing means, said strand-sensing means comprising a stop motion that is operatively associated with machine control means, whereby the amount of strand passing through said yoke is determinative of continued operation of the machine.

More specifically, the present invention relates to a card stop motion comprising a yoke having an apex and two leg portions depending downwardly therefrom, one of said leg portions having incorporated therein a light-transmitting means and the other of said legs having incorporated therein a light-sensitive device, said light-sensitive device being excited by the presence of light whereby upon receiving light transmitted from said light-transmitting means the light-sensitive device becomes excited and triggers an electronic machine controlcircuit.

The apparatus of the present invention is referred to herein as a stop motion system. Ordinarily, this title is correct though the present apparatus can be designed so as to provide other functions in addition to or in lieu of a stop motion function. For instance, the strand-sensing means may be operatively associated with autoleveling systems, with quality control systems, etc., such that upon the sensing of a certain result in the sliver or strand being produced, the output from the strand sensing means verifies the result and the system connected to the strand-sensing means takes the appropriate predetermined action; This-action may be to stop the machine, to adjust the speed of the machine, to adjust the feed to the machine, etc. Hence the apparatus of the present invention may be most generally referred to as a control system for a strand-handling machine.

Whether signaling a stop for the machine or signaling for corrective action, the strand-sensing means may bethe same. A photosensitive strand-sensing means is preferred and generally comprises a system wherein light transmitted from one leg of the yoke excites a photocell in the opposite leg of the yoke unless the beam of light is interrupted in the strand passage by a predetermined amount of strand. Also, however, other strand-sensing systems may be employed, such as, for example, sonic systems, electrical capacitance systems, fluidic logic systems, fiber optics systems, or the like. In fact any sensing system may be incorporated into the yoke of the present invention that is capable of sensing the presence or absence of a predetermined amount of strand in the stran passage that is defined by the yoke.

The term strand as used herein is meant to include any indeterminate length of textile material, such as for instance, fibers, yarn, rope, tow, sliver, filament, yarn bundles, and the like. Thus the stop motion system of the present invention is not restricted to use with a carding machine, but may be associated with any strand-handling machine. Exemplary of strand-handling machines are carding machines, spinning frames, roving frames, twisters, winders, rope producing machines, extrusion units, or the like.

The yoke of the present invention serves as a guide as well as a stop motion system. As such, the yoke is constructed so as to permit contact with the strand without damaging the strand. In the context of a carding system, sliver passes through the yoke and is guided upwardly to a coiler head which distributes the sliver into a sliver can. The coiler head is located in a plane higher than the yoke and operates at such a speed that tension is maintained on the sliver sufficient to retain the sliver in the strand passage of the yoke and adjacent the apex of the yoke.

In addition to the yoke stop motion just described, a slivermonitoring device may be combined with the system. Such a monitoring device is'mounted adjacent the coiler head and comprises a wheel having a peripheral strand-receiving groove. A reed switch or other suitable proximity switch is mounted adjacent the heel to be periodically actuated during rotation of the wheel by switch means mounted thereon. The proximity switch is integral with a pulse counter circuit that mathematically treats the pulses to provide a counter output in predetermined increments. Each pulse to the counter can be regulated to represent any desired increment of length, and the counter output may then be used to calculate machine production, efficiency, etc.

DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a perspective view of a preferred arrangement of the present invention on a carding machine.

FIG. 2 is a side view of a yoke according to the teachings of the present invention.

FIG. 3 is an end view of a sliver wheel assembly according to the teachings of the present invention.

FIG. 4 is a schematic diagram of the circuitry of a preferred arrangement of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As mentioned earlier, the apparatus of the present invention may have incorporated therein any of several types of strandsensing systems and may be used solely as a stop motion or may be used as input to machine control systems. It is preferred to use the present invention as a stop motion system in a carding environment. Accordingly, making reference to FIGS. 1 through 4, the following specific description of the present invention will be directed to a carding stop motion.

'FIG. 1 generally shows a preferred arrangement of the apparatus of the present invention. A textile-carding machine generally indicated as is shown in operation with a web of fibers W exiting from the peeler roll 12 and being transformed into a sliver S by the action of a condenser (not shown) and calendar rolls 14 and 15. Positioned adjacent and in front of calendar rolls 14 and 15 is a yoke stop motion which may be more clearly seen in FIG. 2. Sliver S passes through yoke 20 under tension, and then travels to a coiler head 16 positioned above a sliver can 17 in which the sliver S is arcuately coiled for storage until needed for further processing.

As the card continues to operate, sliver is continually produced and must be packaged for future processing. Several situations may possibly develop that, unless noticed immediately may prove detrimental to the apparatus per se, the produced sliver and also the production efficiency in the card room. For instance the sliver could break between the calendar rolls and the coiler head; a lap up could occur around one or more of the carding rolls; feed of textile material to the card could be disrupted; or the coiler head could become clogged. All of the aforementioned occurrences plus others not mentioned must be detected as soon as possible after occurring to facilitate good and proper operation of the card. A single stop motion system is not adequate for immediate detection of all the aforementioned faults. Needless to say, however, the more coverage obtainable by a single instrument or instrument system, the simpler and more efficient the operation will be. The present invention provides a, stop motion system that does cover a great number of these listed faults and upon detection, immediately initiates the action necessary to implement their correction and the return of the card into production service.

FIG. 2 illustrates a preferred yoke into which is integrally manufactured the strand sensing portion of the present stop motion system. Yoke 20 is comprised of a base 21 and two depending leg members 22 and 23 which define a sliver passage indicated as 24. The interior portions 21, 22 and 23' of base 21 and leg members 22 and 23 respectively are beveled so as to remove any sharp edges from the sliver contact portions of yoke 20. A control box B is shown attached to yoke 20. Control box B contains certain electrical components of the stop motion system and is attached to yoke 20 for convenience. These components could just as well be incorporated into the yoke or positioned in a container separate from yoke 20. Control box B does contain a light source (not shown) and a switch 171 to initiate a long time delay sequence that will be discussed in more detail hereinafter. The light source (not shown) is adjacent a light-conducting member 25 that is shown in phantom in F l6. 2 through the light source could be incorporated into the leg portion of yoke 20. Immediately across the sliver passage 24 is a light-sensitive means 26, also shown in phantom, and electrical conductors 62 and 63 that connect the light-sensitive means 26 to the pertinent circuitry of the stop motion system. Yoke 20 may be fabricated in any desired manner so long as certain prerequisites are met. For instance, the surface should have a smooth finish to avoid disrupting the flow of product therethrough. Also materials of construction should be such that no static charge is built up in the yoke. Further the yoke should be of sufficient strength to withstand inadvertent blowsfrom wrenches, etc. Suitable sensitive member 26. Lucite and plexiglas rods have been found to be very effective. Should the light source be incorporated into the yoke leg, a light conducting member 25 may not be required for successful operation of the present invention. The light sensitive member may be any of a number of devices that, upon excitation by a predetermined amount of light, undergoes an electrical change sufficient to initiate action in accompanying stop motion circuitry. A photocell that experiences a progressive decrease in electrical resistance when subjected to a greater amount of light is preferred for the instant system, though a photocell could be used that becomes excited when light is excluded from the cell, providcd that the accompanying circuitry is modified ac cordingly.

A preferred embodiment of the present invention employs a photocell that becomes excited when it receives a certain amount of light. Accordingly, as sliver S passes through sliver passage 24 of yoke 20, the presence of the sliver disrupts at least a major portion of the light beam and hence prevents its projection by light conducting means 25 onto photosensitive means 26. As mentioned earlier, sliver S is under tension as it passes through yoke 20. Tension on the sliver thus causes the sliver to ride against the beveled portions 21', 22 and 23 of base 21, and legs 22 and 23.ln the event the tension on sliver S is lessened, sliver S drops away from the upper portion of sliver passage 24 and the photocell receives light and initiates action to stop the card. Under normal operation, one would expect some fluctuation in the position of the sliver due to minor tension variation, general area vibration or the like. Such fluctuation may be of sufficient magnitude to permit excitation of the photocell which would stop the card and produce an unwanted, false stop, since no real malfunction had occurred. The present stop motion system has a short time delay circuit incorporated therein to bypass these false stops. Basically the time delay feature overrides actuation of the stop motion during normal sliver fluctuation without signaling a stop for the card. The time delay feature will be more fully discussed hereinafter.

A very important feature of the present invention is the particular design of the yoke. A great deal of fly, lint and trash is inherently present in any area where textile strands arebeing processed. Granted, all modern textile mills and the majority of the older facilities are equippedwith suction devices for the removal of the fly, lint, etc. from the area. Removal, however, is periodic and between passes of the cleaning equipment, these unwanted materials tend to collect in areas, such as certain machinery parts, wires, etc., that are out of range or blocked from the effective field of the cleaning equipment. Further, the fly, lint etc., tends to collect on oily, greasy surfaces and be held thereby against the suction removal action of the cleaning equipment. Accordingly, these materials may interfere with the successful operation of normal stop motions. For instance, a photocell could become covered to continuously block out light, a resistance-measuring device could be rendered ineffective by the presence of the waste or mechanical devices could be blocked from movement by collection of waste in pivotal areas. The present stop motion system is not effected in the least by the presence of waste, even where suction-cleaning equipment is not employed. Hence the present stop motion will continue to operate properly under virtually any condition.

Light conducting member 25 and the light-sensitive member 26 are both mounted so that their surfaces opening into the sliver passage 24 are almost flush with beveled edges 22' and 23'. Continuous movement of sliver through sliver passage 24 produces moving contact between sliver S and light-conducting member 25 and light-sensitive member 26 whereby the exposed surfaces of members 25 and 26 are con tinuously cleaned and even polished to a minor extent. This continuous cleaning action renders the stop motion more efficient and alleviates the possibility of a malfunction due to shielding of the light source or photocell due to the presence of accumulated waste. Moreover, yoke 20 is mounted to the card frame in the same general attitude as shown in FIGS. 1 and 2. Any collection of waste is thus avoided since there are not operationally important areas of yoke where waste may accumulate.

Another important feature of the present invention is the particular association of light source L. Light source L is connected in series with the power source 200 as may be seen in FIG. 4. Such a connection is desirable in that the system will not operate if the bulb in the light source becomes spent. This arrangement thus prevents an operator from bypassing the stop motion by removal of the bulb from light source L.

In addition to photocell excitation when the sliver falls out of yoke 20, the photocell may also become excited when too little sliver S passes through sliver passage 24. Web W in FIG. 1 may, for instance incur a separation of several inches across its width due to a partial lap up of fiber around the doffer, carding cylinder or some other part of the card. If this lap up continues to exist, the pressure produced by excess fiber build up will very likely cause damage to the affected part of the card, particularly the card clothing. Such damage will then necessitate the removal of the card from productionwhile the damaged components are replaced or repaired. lt is therefore very important to detect these faults as soon as they occur, whereby the malfunction can be corrected before any of the machine components are damaged. A lap up of a particular predetermined size will be detected by the present stop motion. Obviously, the presence of the lap up will cause the sliver being produced to be smaller in diameter. Depending upon the sensitivity of the light sensitive means 26, an amount of light less than total projection may be used to trigger the stop motion circuitry. Hence, the system may be adjusted to stop the card when this certain amount of light, less than full exposure, is received by the photocell as would be caused by a smaller size sliver being produced. Referring to FIG. 2, various positions of sliver may be seen. Normal sliver appears in solid lines and is designated S. It may be readily seen that light is prevented from exciting photosensitive member 26 where sliver S is passing through yoke 20. A smaller sliver S is shown in phantom in sliver passage 24. This smaller sliver may have resulted from a lap up somewhere in the card and the photocell 26 will be excited to stop the card. Further sliver S" is shown in phantom at the lower part of sliver passage 24. The position of sliver S" would probably result from reduced tension on the sliver to allow it to drop. With sliver in this position the card would also be stopped.

Sliver S, after leaving yoke 20 travels to a coiler head 16. Coiler head 16 is positioned above a sliver can 17 and in a plane higher than yoke 20. The ascent found in the travel path of sliver S thus forces and maintains sliver S against the uppermost part of sliver passage 24 as previously mentioned. Just prior to entering coiler head 16, sliver S passes over and causes to rotate a sliver wheel 30. Wheel performs a dual function of a back up stop motion and a production counter. Wheel 30 is rotatably mounted on shaft 39 that is journaled in a support frame 16' to which coiler head 16 is attached. The peripheral surface 31 of wheel 30 is concave to receive sliver S and prevent lateral movement of sliver S as it passes over wheel 30. No motive power is required for rotation of wheel 30 since tension on sliver S is sufficient when coupled with the sliver contact area of wheel 30 to cause Wheel 30 to rotate without any appreciable losses due to slippage. Consequently, rotation of wheel 30 is directly proportional to the amount of sliver being produced, and though any size wheel may be used as desired, a preferred wheel has a circumference, measured around the bottom of the concave peripheral surface 31, of 1 foot. One rotation of wheel 30 thus indicates the production of 1 linear foot of sliver.

A magnet 32 is attached to a portion of wheel 30 as shown in phantom. Magnet 32 moves at the same linear velocity as does sliver S and as magnet 32 passes a magnetically sensitive switch means 34, one rotation of wheel 30 is recorded. Specific circuitryfor recording the pulses produced in the proximity switch 34 will be more fully discussed hereinafter.

Sliver wheel 30 may therefore be used to tally the production of a particular card for planning purposes or operator incentive purposes. The use of a magnet and a magnetically sensitive switch as discussed above is the preferred embodiment. Obviously any suitable switch assembly may be employed that will produce pulses as the sliver wheel rotates. Likewise, the number of switch assemblies positioned around the wheel are discretionary.

A particularly good feature of the sliver wheel for determining the amount of sliver produced by a card is the stop motion capability of the wheel. Wheel 30 is so operated that cessation of rotation triggers the same stop motion circuit being served by the yoke stop motion and stops the card. An operator cannot therefore bypass the sliver wheel in the sliver path to avoid the determination of production by the card. Circuitry associated with the sliver wheel generates a stop motion pulse during each rotation of the wheel, resulting in a continuous train or series of pulses. If the continuity of the series of pulses is interrupted for a time in excess of a certain predetermined anticipated time, the stop motion circuitry will be triggered and the card stopped. Stop motion capability for the sliver wheel also provides a good back up system for the yoke stop motion. For example, should the sliver break and be wedged in sliver passage 24 of yoke 20, wheel 30 will not rotate and will thus trigger the stop motion since its only motive power is supplied by the movement of sliver S thereover. It is therefore highly improbable that the present stop motion system could be bypassed undetected as might sometimes be tried by operating personnel to avoid multiple stops for a troublesome piece of equipment.

Combined circuitry for the present invention may be seen in FIG. 4. A breakdown of the circuitry generally shows a photocell trigger circuit (A); a flip-flop (B); an SCR controlled signal lamp circuit (C); an SCR controlled high-speed clutch circuit (D); an SCR controlled low-speed clutch circuit (E); a long time delay and tramp metal circuit (F); a sliver wheel pulse generating and trigger circuit (G), and an SCR controlled pulse counter circuit (H).

The photocell trigger circuit (A) is comprised of a suitable light responsive photocell 26 in series with a resistor 102 and a variable resistor 103. A capacitor 104 is connected in parallel with the photocell 26 and resistor 102 and provides the short time delay element to compensate for normal flutter variation of sliver passing through yoke 20. Photocell 26, resistor 102 and capacitor 104 are connected to the base of a transistor 105 which, when turned on, triggers the stop motion circuit through flip-flop (B) and simultaneously causes signal lamp to be energized through its SCR controlled circuit (C).

Flip-flop (B) is comprised of two transistors 11] and 112 which are connected to be bistable. in the normal operating condition, transistor 111 is oft" and transistor 112 is on. Flipflop (B) also contains resistors 114, 115, 116 and 117.

Clutch circuits (D) and (E), lamp circuit (C) and counter circuit (H) are identical with two exceptions. This circuitry will therefore be described jointly with the exceptions being noted. All reference characters will be the same as those below for lamp circuit (C) except for different 100 prefixes. Both clutches, the lamp and the counter operate on rectified alternating current from a source 200. Basically each circuit contains a silicon controlled rectifier (SCR) that controls the power input through the clutches, lamp or counter. Common emitter connected transistors 141 and 142 are arranged to receive input to the circuitry to gate the SCR 140 and allow current flow through the various intended components. Gating of SCR 140 is not accomplished by a single pulse arrangement, but is accomplished through a combined capacitor 144-Silicon Bilateral Switch (SUS/SBS) 145 arrangement. The SCR is thus gated early during each half cycle of the rectified AC to compensate for turning off of the SCR when current therethrough falls below the minimum holding current value for the SCR.

vNoted exceptions in the above-described circuits are found in the signal lamp circuit (C) and the high-speed clutch circuit (D). Lamp circuit (C) does not have a diode rectifier in parallel with the bulb as is found with the remainder of the clutch and counter circuits. Also the high-speed clutch circuit (D) contains an extra feature not found in the other circuits. After the card has been stopped due to a malfunction or for any reason, and startup procedures are underway, the card is automatically started at slow speed, utilizing only the low speed clutch. This feature is provided by an inhibit or hold off circuit 249 that inverts its input from the long time delay circuit for the length of the time delay, whereby the high-speed clutch SCR is not gated and the clutch is not energized. At the end of the time delay sequence, the inversion through inhibit circuit 249 ceases and SCR 240 is gated via the normal circuitry to energize high-speed clutch 130 and operate the card at its normal or high-speed rate.

It should also be noted that counter circuit (H) shown in FIG. 4 can be varied according to the desires of the individual. Specifically, according to the desired increment to be recorded from the pulses generated by wheel 30, it may be necessary to adjust the pulses to the counter to coincide with the predetermined increment of strand production. This procedure is well within the purview of those skilled in the art,

however, and there is no need to elaborate on the possible electronic modification for dividing or otherwise adjusting pulse input to counter circuit (H).

The long time delay and tramp metal circuit (F) provide dual functions. The tramp metal feature is of course added to detect the presence of metal in the web as it passes through the carding machine. By grounding one roll and insulating one roll, metal passing through the system completes the circuit at 170 and causes a stop. Detection of metal in the web is quite important for successful operation of the card and the tramp metal portion of the circuit is so designed to override the long time delay if metal is detected. The long time delay has been incorporated into the present circuitry for restarting of the card and must be activated for each restart. The long time delay circuit comprises switch 171, transistor 172, capacitor 173 a Darlington transistor arrangement 174 and transistors 175 and 176. Voltage divider conductors 177, 178 and 179 associate the long time delay circuit (F) with flip-flop (B) and both clutch circuits (D) and (E).

Pulse-generating circuit (G) is associated with sliver monitor wheel 30 and generates a pulse for each actuation of reed switch 34. Circuit (G) is comprised of transistor 181 that is AC coupled through capacitor 182 to counter circuit (H) and through capacitor 183 to transistors 184 and 185. Transistors 184 and 185 are in turn connected to lamp circuit (C) and flip-flop (B).

Now that the apparatus and circuitry of the present invention have been described, the operation of the present invention will be discussed. Under normal operating conditions the 7 card operates at full speed with both the high-speed clutch 130 and the low speed clutch 150 energized. A web of fiber exits from peeler roll 12 and is condensed and passes between calendar rolls 14 and 15 to form a sliver S. After leaving calendar rolls 14 and 15 sliver S passes through sliver passage 24 of yoke adjacent light-conducting means 25 and lightsensitive member 26. Sliver S is held against yoke 20 by tension on the sliver between calendar rolls 14 and 15 and coiler head 16. Just prior to entering coiler head 16, sliver S passes over at least a portion of sliver wheel 30, being held in concave peripheral surface 31, and causes wheel to rotate whereby magnet means 32 operates magnetically actuated switch means 34 to pulse a counter means (H) and record sliver production from the particular card.

When a malfunction occurs that causes sliver S to break, to lose tension, or to become smaller in diameter, sliver S no longer bisects the light being projected from light-conducting means 25 and light source L and light is projected across sliver passage 24 onto light sensitive means 26 to excite same. Excitation of the photocell 26 lowers the resistance of the photocell and permits a pulse to turn on transistor 105. Transistor 105 is not, however, immediately turned on. in-

stead, capacitor 104, which has been charged during normal operation of the machine, loses its charge when the resistance of photocell 26 is lowered, to maintain the state of bias on transistor in the circuit for a short period of time. The capacitor drain thus provides a time delay sufficient to permit cessation of excitation of photocell 26 and return of the photocell resistance if, in fact, the excitation was caused by normal sliver fluctuation. After the short time delay period elapses, transistor 105 is turned on and pulses transistor 1110f flip-flop (B) through conductors 106 and 113 to turn on transistor [11. The turning on of transistor 111 automatically causes transistor 112 to be turned off. A low-impedance current path is created through transistor 111 thus removing drive from the base of transistor 24] of clutch circuit (D) and transistor 341 of clutch circuit (B) through conductors 119 and 119'. Absence of drive current at the base of transistors 241 and 341 results in their being turned off by bias resistors 241' and 341 respectively. Transistors 242 and 342 are thus turned on creating a short circuit therethrough which prevents gating of SCR 240 and SCR 340. With no gating of the SCRs, they will be commutated when load current thereto falls below the holding current value and current ceases to flow to clutches and 150. The card then ceases to run.

Simultaneously with the triggering of flip-flop (B), the lamp circuit (C) is pulsed by transistor 105 through conductor 107 whereby through the action of transistors 141 and 142, capacitor 144 and SUS/SBS 145, the SCR is periodically gated, thus supplying the necessary current for excitation of 7 signal lamp 120 to indicate that the card has stopped running. Lamp 120 continues to burn until the card is restarted and transistor 105 is turned off due to a return of the photocell 26 to a high-resistance state.

After the particular malfunction has been corrected and the operator is ready to return the card to production, the card cannot be restarted except through actuation of the long time delay circuit (F). The long time delay circuit (F) provides for uninterrupted running of the card at slow speed while web, sliver, etc., are pieced up for normal operation. The long time delay overrides the photocell circuit and prevents a false stop of the machine. Simultaneously during the long time delay, the card is inhibited from operating at high speed by an inhibit circuit 249 associated with the high-speed clutch circuit (D) and being operated through the time delay circuit (F). As soon as the delay circuit time constant has run, the inhibit circuit is deactivated and the card returns to normal high-speed production with both the high and low speed clutches 130 and respectively being operational.

Operation of the long time delay circuit is begun by closing switch 171 which allows capacitor 173 to become charged. Capacitor 173 then discharges to turn the Darlington arrangement 174 on whereby it is short circuited and transistor 175 is turned on. Output from transistor'175 is then divided between conductors 177, 178 and 179. Conductor 179 provides input to transistor 341 of low speed clutch circuit (E) to gate SCR 340 and permit operational current flow to clutch 150. Conductor 178 provides input to inhibit circuit 249 of high-speed clutch circuit (D). Inhibit circuit 249 inverts the input which prohibits actuation of high-speed clutch 130. Input to flip-flop (B) is provided via conductor 179 to turn on transistor 112 and turn off transistor 111, ergo return all clutches to the operational state. Output from transistor 175 of circuit (F) continues only so long as capacitor 173 discharges. After discharge of capacitor 173, Darlington 174 then returns to its original state and the circuit ceases to function as described above. Since no input is now received by inhibit circuit 249, the inverted output to circuit (D) ceases and is replaced by an operational input through flip-flop (B) which also feeds low speed clutch circuit (E) for normal operation of the card.

Tramp metal, as mentioned earlier, may be detected in the cards feed system and the card should be stopped before the metal passes the feed roll into the card. A suitable metal detector circuit may be included with the stop motion system of the present invention. In such a metal detector circuit,

completion of the circuit at contacts 170 by tramp metal between a grounded member and an insulated member actuates the tramp metal portion of the circuit which will override the long time delay to stop the card. Once the time delay has been actuated, no other means are provided for performing the override function since the basic purposes of the time delay is to prevent false stops during start up of the carding machine.

As the normal operation of the carding machine proceeds, sliver S leaves yoke and passes upwardly into contact with sliver wheel 30. As sliver passes, under tension, over the concave periphery 31 of wheel 30, wheel is caused to rotate at a speed directly proportional to the speed of the passing sliver S. Magnet 32 attached to wheel 30 passes a magnetically sen sitive switch 34 once during each rotation of wheel 30. Switch 34, which mayvery suitably be a hermetically sealed reed switch, is closed as magnet 32 passes and reopens after the magnetic influence ceases. Accordingly, the circuit (G) is completed when switch 34 is closed and transistor 181 is turned on by input from conductor 186 and then charged capacitor 182 which is AC coupled to counter circuit (H) through conductor 187. Capacitor 182 therefore provides input to transistor 441 of circuit (H) which turns off transistor 442 and hence provides gating input to SCR 440 through capacitor 444 and SUS/SBS 445 to register a pulse at counter 160. Counter 160 can be designed, using electronic division techniques so as to read out in any increment that might be desired.

Circuit (G) is also provided with a stop motion trigger circuit to become actuated when wheel 30 ceases to rotate. During the pulse period, when switch 34 is closed, capacitor 188 is also charged. Discharge of capacitor 188 is then timed to be less than complete by the next closing of switch 34 when it will be recharged. in the event that wheel 30 has ceased to turn, capacitor 188 will discharge completely after which transistor 185 will become turned on to supply input to flip-flop (B) through conductor 189 to stop the carding machine as described above and to energize signal light 120 via conductor 190 to indicate stopping of the card.

The present invention having been described, it should be pointed out that numerous variations may be made to the system without departing from the spirit of the invention. For instance, while the drive system presently illustrated includes a low speed clutch and a high-speed clutch, numerous other systems may be advantageously employed. illustrative of other suitable drive systems which could be controlled by the stop motion or control systems of the present invention are a hydraulic drive, a stepper motor operated through a translator, a DC motor drive, motors controlled by solenoid systems, motors controlled by pneumatic systems, a positive infinite variable drive, and the like. Further, an audible signal may be utilized to indicate a machine stop, either in combination with or in lieu of the lamp signal shown in FIG. 4. Lastly, as previously discussed, the strand sensing means of the present invention may be utilized to provide input to control systems such as an autoleveling system, a remote quality control monitor, or the like.

What is claimed is:

1. Apparatus for controlling the operation of a strand-handling machine comprising:

a. a yoke, said yoke comprising a base having two leg portions depending downwardly therefrom, said base and said leg portions defining a strand passage;

b. strand-sensing means associated with said strand passage;

and

c. machine control means responsive to output from said strand-sensing means.

2. Apparatus for controlling the operation of a strand-handling machine as defined in claim 1 wherein the surfaces of said yoke adjacent the strand passage are beveled and the yoke also serves as a strand guide.

3. Apparatus for controlling the operation of a strand-handling machine as defined in claim 1 wherein the strand-sensing means is integral with at least one of the leg portions of said yoke.

4. Apparatus for controlling the operation of a strand handling machine as defined in claim I wherein the strand-sensing means is a stop motion.

5. Apparatus for controlling the operation of a strand-handling machine as defined in claim 4 wherein the stop motion is a photoelectric stop motion.

6. Apparatus for controlling the operation ola strand'handling machine as defined in claim 5 wherein a light-transmitting member is located in one leg of said yoke and a photocell is located in the other leg of said yoke.

7. Apparatus for controlling the operation of a strand-handling machine as defined in claim 5 wherein the light-transmitting member is an elongated lucitc member.

8. Apparatus for controlling the operation of a strand-handling machine as defined in claim 6 wherein the light-transmitting member is an elongated plexiglass member.

9. Apparatus for controlling the operation of a strand-handling machine as defined in claim 1 wherein the machine control means comprises:

a. a trigger circuit responsive to said strand-sensing means;

b. a flip-flop responsive to said trigger circuit;

c. a signal circuit responsive to said trigger circuit;

d. a drive means circuit responsive to said flip-flop; and

e. a restart circuit operatively associated with said drive means circuit and having a long time delay constant incorporated therein.

10. Apparatus for controlling the operation of a strand-handling machine as defined in claim 9 wherein the trigger circuit has a short time delay constant incorporated therein to compensate for normal strand flutter.

11. Apparatus for controlling the operation of a strand-handling machine as defined in claim 9 wherein the signal and drive means circuits are controlled by silicon controlled rectifiers. v

12. Apparatus for controlling the operation of a strand-handling machine as defined in claim 1 comprising further strandcounting means.

13. Apparatus for controlling the operation of a strand-handling machine as defined in claim 12 wherein the strandcounting means comprises a rotatably mounted wheel having a strand-engaging periphery; said wheel having associated therewith proximity switch means and proximity switchactuating means for creating counting pulses as said wheel is rotated.

14. Apparatus for controlling the operation of a strand-handling machine as defined in claim 13 wherein the strand-engaging periphery of said wheel is concave.

15. Apparatus for controlling the operation of a strand-handling machine as defined in claim 13 wherein the proximity switch is a reed switch and the proximity switch-actuating means is a magnet.

16. Apparatus for controlling the operation of a strand-handling machine as defined in claim 12 wherein the machine control means comprises:

a. a trigger circuit responsive to said strand-sensing means,

b. a flip-flop responsive to said trigger circuit;

0. a signal circuit responsive to said trigger circuit;

d. a drive means circuit responsive to said flip-flop and dietating the operational state of the drive means;

e. a restart circuit operatively associated with said drive means circuit and having a long time delay constant incorporated therein;

f. a pulse generating circuit responsive to said counting means, said pulse-generating circuit also having a stop motion circuit therein that is associated with said flipflop; and

g. a pulse-counting circuit responsive to said pulse-generat' ing circuit.

17. Apparatus for controlling the operation of a strand-handling machine as defined in claim 9 wherein the drive means circuit comprises a low speed clutch drive circuit and a highspeed clutch drive circuit.

l8. Apparatus for controlling the operation of a strand-handlingmachine as defined in claim l6 wherein the drive means circuit comprises a low speed clutch drive circuit and a highspeed clutch drive circuit.

19. Apparatus for controlling the operation of a strand-handling machine as defined in claim 17 wherein said high-speed clutch drive circuit alsoincludes an inhibit circuit to delay operation of the high-speed clutch during start up of the machine.

20. Apparatus as defined in claim 1 wherein the strand-handling machine is a textile-carding machine.

21. Apparatus for controlling the operation of a strand-handling machine as defined in claim 1 wherein the strand-handling machine is a carding machine; the strand-sensing means comprises a photoelectric stop motion system, said photoelectric stop motion system comprising a light source, a light-conducting member integral with one leg of said yokeand a photocell integral with the other leg of said yoke, said lightconducting member being positioned so as to direct light across said strand passage onto said photocell during the absence of a predetermined amount of strand in said strand 7 passage; and the machine control means comprises:

a. a trigger circuit responsive to said photocell;

b. a flip-flop responsive to said trigger circuit;

c. a signal circuit responsive to said trigger circuit;

d. a drive means circuit responsive to said flip-flop; and

e. a restart circuit operatively associated with said drive means circuit and having a long time delay constant incorporated therein.

.22. Apparatus for controlling the operation of a carding machine as defined in"claim 2i further comprising a stra'ridcounting means, said strand-counting means comprising a rotatably mounted wheel having a concave strand-engaging periphery, said wheel also having mounted thereon a magnet, and a reed switch mounted adjacent said wheel, and wherein the machine control means further comprises a pulse-generating circuit responsive to said reed switch and a pulse-counting circuit responsive to said pulse-generating circuit.

23. A control circuit for a strand-handling machine com prising:

a. strand-sensing means;

b. a trigger circuit responsive to actuation of said strandsensing means, said trigger circuit having a short time delay incorporated therein to compensate for fluctuation of strand being sensed;

c. a flip-flop, responsive to said trigger circuit;

d. a signal circuit responsive to said trigger circuit;

e. a machine drive means circuit responsive to said flip-flop;

and

f. a restart circuit operatively associated with other of said circuitry, said restart circuit overriding said trigger circuit and inhibiting high-speed operation of drive means controlled by said drive means circuit during start up.

24. A control circuit for a strand-handling machine as defined in claim 23 wherein said drive means circuit comprises a low speed clutch drive circuit and a high-speed clutch drive circuit. 

1. Apparatus for controlling the operation of a strand-handling machine comprising: a. a yoke, said yoke comprising a base having two leg portions depending downwardly therefrom, said base and said leg portions defining a strand passage; b. strand-sensing means associated with said strand passage; and c. machine control means responsive to output from said strand-sensing means.
 2. Apparatus for controlling the operation of a strand-handling machine as defined in claim 1 wherein the surfaces of said yoke adjacent the strand passage are beveled and the yoke also serves as a strand guide.
 3. Apparatus for controlling the operation of a strand-handling machine as defined in claim 1 wherein the strand-sensing means is integral with at least one of the leg portions of said yoke.
 4. Apparatus for controlling the operation of a strand-handling machine as defined in claim 1 wherein the strand-sensing means is a stop motion.
 5. Apparatus for controlling the operation of a strand-handling machine as defined in claim 4 wherein the stop motion is a photoelectric stop motion.
 6. Apparatus for controlling the operation of a strand-handling machine as defined in claim 5 wherein a light-transmitting member is located in one leg of said yoke and a photocell is located in the other leg of said yoke.
 7. Apparatus for controlling the operation of a strand-handling machine as defined in claim 5 wherein the light-transmitting member is an elongated lucite member.
 8. Apparatus for controlling the operation of a strand-handling machine as defined in claim 6 wherein the light-transmitting member is an elongated plexiglass member.
 9. Apparatus for controlling the operation of a strand-handling machine as defined in claim 1 wherein the machine control means comprises: a. a trigger circuit responsive to said strand-sensing means; b. a flip-flop responsive to said trigger circuit; c. a signal circuit responsive to said trigger circuit; d. a drive means circuit responsive to said flip-flop; and e. a restart circuit operatively associated with said drive means circuit and having a long time delay constant incorporated therein.
 10. Apparatus for controlling the operation of a strand-handling machine as defined in claim 9 wherein the trigger circuit has a short time delay constant incorporated therein to compensate for normal strand flutter.
 11. Apparatus for controlling the operation of a strand-handling machine as defined in claim 9 wherein the signal and drive means circuits are controlled by silicon controlled rectifiers.
 12. Apparatus for controlling the operation of a strand-handling machine as defined in claim 1 comprising further strand-counting means.
 13. Apparatus for controlling the operation of a strand-handling machine as defined in claim 12 wherein the strand-counting means comprises a rotatably mounted wheel having a strand-engaging periphery; said wheel having associated therewith proximity switch means and proximity switch-actuating means for creating counting pulses as said wheel is rotated.
 14. Apparatus for controlling the operation of a strand-handling machine as defined in claim 13 wherein the strand-engaging periphery of said wheel is concave.
 15. Apparatus for controlling the operation of a strand-handling machine as defined in claim 13 wherein the proximity switch is a reed switch and the proximity switch-actuating means is a magnet.
 16. Apparatus for controlling the operation of a strand-handling machine as defined in claim 12 wherein the machine control means comprises: a. a trigger circuit responsive to said strand-sensing means; b. a flip-flop responsive to said trigger circuit; c. a signal circuit responsive to said trigger circuit; d. a drive means circuit responsive to said flip-flop and dictating the operational state of the drive means; e. a restart circuit operatively associated with said drive means circuit and having a long time delay constant incorporated therein; f. a pulse generating circuit responsive to said counting means, said pulse-generating circuit also having a stop motion circuit therein that is associated with said flip-flop; and g. a pulse-counting circuit responsive to said pulse-generating circuit.
 17. Apparatus for controlling the operation of a strand-handling machine as defined in claim 9 wherein the drive means circuit comprises a low speed clutch drive circuit and a high-speed clutch drive circuit.
 18. Apparatus for controlling the operation of a strand-handling machine as defined in claim 16 wherein the drive means circuit comprises a low speed clutch drive circuit and A high-speed clutch drive circuit.
 19. Apparatus for controlling the operation of a strand-handling machine as defined in claim 17 wherein said high-speed clutch drive circuit also includes an inhibit circuit to delay operation of the high-speed clutch during start up of the machine.
 20. Apparatus as defined in claim 1 wherein the strand-handling machine is a textile-carding machine.
 21. Apparatus for controlling the operation of a strand-handling machine as defined in claim 1 wherein the strand-handling machine is a carding machine; the strand-sensing means comprises a photoelectric stop motion system, said photoelectric stop motion system comprising a light source, a light-conducting member integral with one leg of said yoke and a photocell integral with the other leg of said yoke, said light-conducting member being positioned so as to direct light across said strand passage onto said photocell during the absence of a predetermined amount of strand in said strand passage; and the machine control means comprises: a. a trigger circuit responsive to said photocell; b. a flip-flop responsive to said trigger circuit; c. a signal circuit responsive to said trigger circuit; d. a drive means circuit responsive to said flip-flop; and e. a restart circuit operatively associated with said drive means circuit and having a long time delay constant incorporated therein.
 22. Apparatus for controlling the operation of a carding machine as defined in claim 21 further comprising a strand-counting means, said strand-counting means comprising a rotatably mounted wheel having a concave strand-engaging periphery, said wheel also having mounted thereon a magnet, and a reed switch mounted adjacent said wheel, and wherein the machine control means further comprises a pulse-generating circuit responsive to said reed switch and a pulse-counting circuit responsive to said pulse-generating circuit.
 23. A control circuit for a strand-handling machine comprising: a. strand-sensing means; b. a trigger circuit responsive to actuation of said strand-sensing means, said trigger circuit having a short time delay incorporated therein to compensate for fluctuation of strand being sensed; c. a flip-flop responsive to said trigger circuit; d. a signal circuit responsive to said trigger circuit; e. a machine drive means circuit responsive to said flip-flop; and f. a restart circuit operatively associated with other of said circuitry, said restart circuit overriding said trigger circuit and inhibiting high-speed operation of drive means controlled by said drive means circuit during start up.
 24. A control circuit for a strand-handling machine as defined in claim 23 wherein said drive means circuit comprises a low speed clutch drive circuit and a high-speed clutch drive circuit. 